foo1((x)=>null
), foo2((x)=>[
        ""
    ]
), foo3((x)=>null
), foo4((x, y)=>""
), foo5((x)=>null
), foo6((x)=>null
), foo11((x, y)=>null
), foo15((x)=>null
), foo16((x)=>null
), foo17((x)=>null
), foo18((x)=>null
);
